Generalize _hists_match for mom6 files

[alperaltuntas]

Changes in _hists_match to fix the failures encountered in comparison phases of MOM6 MCC tests:

• Extend matching to files without datestamps.
• Support matching instance numbers formatted as ._000X.

Test suite: aux_mom
Test baseline: 30beta02
Test namelist changes: none
Test status: [bit for bit, roundoff, climate changing] b4b

Fixes [CIME Github issue #] ESCOMP/MOM_interface#169

User interface changes?: none

Update gh-pages html (Y/N)?: N

[alperaltuntas]

@jedwards4b, this PR fixes: ESCOMP/MOM_interface#169 when evaluated in conjunction with ESCOMP/MOM_interface#183

All of the following tests passed:
MCC_D_Ld2.TL319_t232.G_JRA.derecho_gnu
MCC.T62_t232.C.derecho_gnu
MCC.ne30pg3_t232.BLT1850.derecho_intel

However the following test fails: MCC.ne30pg3_t232.BLT1850.derecho_gnu, even though its intel counterpart passes. The error I get is from CMEPS, and I think is unrelated to MOM6, and likely has to do with variable initializations in CMEPS.

20240818 102432.593 ERROR            PET6331 /glade/work/altuntas/cesm.sandboxes/cesm3_0_beta02.sbx/components/cmeps/cime_config/../mediator/med_methods_mod.F90:2628 ERROR: 6 nans found in Sa_pslv
20240818 102432.594 ERROR            PET6331 /glade/work/altuntas/cesm.sandboxes/cesm3_0_beta02.sbx/components/cmeps/cime_config/../mediator/med_methods_mod.F90:2633 ABORTING JOB
20240818 102432.594 ERROR            PET6331 /glade/work/altuntas/cesm.sandboxes/cesm3_0_beta02.sbx/components/cmeps/cime_config/../mediator/med_phases_prep_ocn_mod.F90:310 Failure  - Passing error in return code

[jedwards4b]

The issue you brought up is a known problem: ESCOMP/CAM#1116

[jedwards4b]

thanks!